The skin is our body's largest organ. It is constantly being renewed and the outer layer of dead cells usually fall of unnoticed. Our skin plays host to a fungus called Pityrosporum ovale, or Malassezia, as it is more commonly known today.

This fungus is found only on humans and is attributed to the cause of dandruff. Ordinarily, it causes no problems, but when it grows too fast, it can cause cells to flake off prematurely and this results in dandruff, itchiness and sometimes a rash.

The causes of this rapid growth of the yeast can be put down to poor rinsing off of shampoo, over use of heated tongs and hair dryers, central heating (causing low humidity), use of alcohol based hair products and diet has also been linked to this problem.

There are a number of medicated shampoos designed to combat dandruff such as 'Head & Shoulders', 'T-Gel Anti-dandruff' and 'Nizoral'.

I should point out that washing your hair twice, as recommended by most shampoo manufacturers, is often said, by tricologists, to only enhance the profits of the shampoo manufacturers. However, in the case of these medicated shampoos, its probably good practice to do so. On the second washing, massage the scalp well for a few mins and even use a fairly stiff hair brush to ensure good coverage. After washing, rinse well with clean water and, in my personal opinion, do not use a conditioner.

BTW, Tea Tree oil is said to be a good natural defense against dandruff.

Actually, it seems to me that washing hair twice (wash, rinse, wash again and rinse) has a different and noticeable effect on your hair from a single wash/rinse so I wonder whether the shampoo manufacturers say this only to enhance profits or whether there is a real point to it afterall. My impression is that the first wash seems to neutralise the natural greases but that the greases also neutralise the detergent action. The second wash seems to change the characteristics of the hair so certainly has an effect. It may even be that use of a small amount of shampoo on a first wash followed by a second wash could be more effective than one wash with a (probably necessary) large amount.

Sorry to hear about your dandruff problems. It is a much underestimated problem. Particularly if you wake up at night due to the warmth causing your hair to itch.

I had terrible dandruff from age 18, I tried all the usual shampoos, head and shoulders, vosene, selsun etc. but nothing worked. I then tried Nizoral, but had some awful side effects, which other people have also had, see newbielink:http://www.retaining-hair-health.com/2009/12/nizoral-ketonazole-shampoo.html [nonactive] for more details (but these are anti androgenic side effects which only affect men) however I found the Schwartzkopf Bonacure anti dandruff lotion to be excellent. You apply it after shampoo but don't wash it off. It works incredibly well (for the record I have no connection with Schwartzkopf or anyone who sells it!)

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